Thermal conductivity of a boron phosphide single-crystal wafer up to high temperature

The thermal diffusivity of a well-characterized boron phosphide (BP) single-crystal wafer made by a chemical vapor deposition process was measured by a unique ring-flash light method. Thermal conductivity calculated from the products of thermal diffusivity, specific heat capacity, and density of the wafer yields a high thermal conductivity of 4.0 W cm−1 deg−1 at room temperature, and shows a pronounced temperature dependence due to phonon scattering. Boron phosphide is a promising material for heat-sink substrates for semiconductor devices.